Support create table

We must support two types of cluster-wide tables:

• global (data is replicated and modified via raft log) - unsupported by sbroad at the moment
• sharded - yes, we can!

SQL:

1. Global table syntax

   create table t (a scalar null, b integer, primary key (a, b)) using memtx
   distributed globally option (timeout = 3.0)
   
   create table t (a scalar, b integer, primary key (a, b)) using memtx
   distributed globally

2. Sharded table syntax

   create table t (a scalar, b integer not null, primary key (a)) using vinyl
   distributed by (a, b) option (timeout = 3)

Lua:

1. Global table syntax

      pico.create_space({
          name = 'friends_of_peppa',
          format = {
              {name = 'id', type = 'unsigned', is_nullable = false},
              {name = 'name', type = 'string', is_nullable = false},
          },
          primary_key = {'id'},
          distribution = 'global',
          timeout = 3,
      })

2. Sharded table syntax

      pico.create_space({
          name = 'wonderland',
          format = {
              {name = 'property', type = 'string', is_nullable = false},
              {name = 'value', type = 'integer', is_nullable = true}
          },
          primary_key = {'property'},
          distribution = 'sharded',
          sharding_key = {'property'},
          timeout = 3,
      })